Method of condensing metallic vapor

ABSTRACT

A method of condensing the gaseous portion of a two-phase metallic stream consisting of liquid droplets and a gas. The method includes the steps of ejecting a metallic liquid through a nozzle at high speed to enclose, with a sheet of the liquid, a rotationally symmetric space which tapers in the direction of flow of the liquid, and directing the two-phase metallic stream into the space.

H N H 3,634,067 Eugen Klein 1,963,295 6/1934 Deutsch 103/265 Bleitreustr 819 Gth-II Tr., 1 Berlin, 12, 2,000,762 5/1935 Kraft 103/267 Germany 2,060,557 11/1936 Davis... 26/D1G. 21 Appl. N0. 748,250 2,190,109 2 1940 Tinker 103/265 221 Filed July 29,1968 3,315,806 4/1967 Sigwart et al. 55/261 Patented Jan. 11, 1972 3,399,511 9/1968 Geiringer 55/84 32 Priority July 29, 1967 2,416,255 2/1947 GrlSOld, .Ir. etal.. 7516? 331 Germany 3,294,989 12/1966 Eichenberger 310/11 31 P 16 01 110.2 3,513,336 5/1970 Prem 310/11 Primary Examiner-Frank W. Lutter 54] METHOD OF CONDENSING METALLIC VAPOR 1 Claim, 1 Drawing Fig Attorney-Spencer & Kaye 521 US. (:1 75/66,

55/72, 55/220, 75/67, 75/88, 261 1 16, 310/1 1 51 Int. Cl c2211 27 00 ABSTRACT: A method of condensing the gaseous P 9f Field 6: Search 55/83, 84, a two-phase metallic stream consisting of liquid droplets and a 72, 220; 261/78, 1 16; 103/264, 265, 252, 263; gas. The method includes the steps of ejecting a metallic liquid 62/500; /67, 66, 88; 310/11 through a nozzle at high speed to enclose, with a sheet of the liquid, a rotationally symmetric space which tapers in the R f r Ciled direction of flow of the liquid, and directing the two-phase UNITED STATES PATENTS metallic stream into the space. 1,004,664 10/1911 Leblanc 2.61/76 PATENTED JAN] 1 1972 lnven/ar: Eugen K Iein BACKGROUND OF THE INVENTION The present invention relates to a method of condensing the gaseous portion of a two-phase stream consisting of liquid droplets and a gas.

When designing thermodynamic circulation apparatus, it is often necessary to condense the gaseous portion of a twophase fluid stream consisting of droplets and steam. A twophase stream of this kind can arise, for example, in a magnetohydrodynamic (MHD) circulation system which employs a single fluid medium when the liquid and the gaseous phase of the medium are present together, usually not in thermodynamic equilibrium.

The most well known method of condensing a gas is to contain the fluid within cooling surfaces from which heat energy is removed. Because of the frictional losses, however, the use of cooling surfaces to condense moving fluids results in a loss of kinetic energy and, in turn, a reduction in the efficiency of the entire system.

Another known way of condensing a gaseous fluid involves the so-called injection" technique, whereby a cold stream of fluid is supplied to the two-phase stream to cool and condense the gaseous part thereof. However, the frictional losses which occur with this method are also considerable.

SUMMARY OF THE INVENTION An object of the present invention, therefore, is to provide a method of condensing the gaseous portion of a two-phase stream without causing substantial losses in kinetic energy due to friction.

This, as well as other objects which will become apparent in the discussion that follows, is achieved, according to the present invention, by ejecting a liquid through a nozzle with an annular cross section to form a rotationally symmetric sheet which tapers in the direction of the liquid flow and directing the two-phase stream into the space enclosed by the sheet.

It is advantageous if the medium which is employed for the liquid jet is the same as that which makes up the two-phase stream. This obviates the otherwise necessity of separating the two streams after the condensation.

The preferred embodiment of the method, according to the present invention, includes a rotationally symmetric condensing tube connected, for example, at the end of a convering out the method according to the present invention, for condensing the gaseous portion of a two-phase stream consisting of liquid droplets and a gas. The figure shows a condensing tube 1 having an opening 2 for receiving the two-phase stream. The direction of flow of the two-phase stream is indicated by the arrow 6.

The stream of liquid 4 enters the tube I at high speed through the nozzle 3. It forms, inside the tube, a rotationally symmetric liquid sheet 5.

In the particular example shown in the figure, the two-phase stream is produced from a superheated liquid in the flow channel 7. This liquid is passed through a convergent-divergent nozzle 8 and initially forms bubbles due to expansion. The bubbles quickly grow and break the fluid into droplets which are accelerated by the expanding steam.

To form the sheet of liquid, it is advantageous if a part of the same liquid which forms the two-phase stream is supplied in the subcooled state through the flow channel 9 to the nozzle 3. Since turbulence in the liquid 4 can lead to instabilities in the liquid sheet 5, a straightener l0 and a sieve 11 can be arranged, if necessary, in the channel 9.

As the two-phase stream passes through the space enclosed by. the sheet of liquid, it condenses and forms a single-phase or liquid stream 12. If the condensing method is employed in an MI-ID generator, for example, and the stream 12 consists of a liquid metal (sodium or potassium), its kinetic energy may then be transformed into electrical energy. I

According to a particular feature of the present invention an annular nozzle 13 is provided coaxially with the nozzle 3 to provide passage for steam or a gas. The steam or gas is fed under pressure through the channels 14 and the nozzle 13 into the space 15 between the liquid sheet 5 and the wall 1 of the condensing tube. By proper selection of the gas pressure in the gent-divergent nozzle which is surrounded by two additional I nozzles of annular cross section. All three nozzles are arranged on a common axis. The convergent-divergent nozzle produces the droplet-steam mixture while the subcooled stream of liquid which forms the sheet is ejected through the inner annular nozzle. The outer annular nozzle serves to supply a gas or steam under pressure to the space between the liquid sheet and the walls of the condensing tube. It is possible, however, to dispense with this outer steam nozzle if all the dimensions of the apparatus are well chosen to provide the proper directionality and stability to the liquid sheet.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE is a cross-sectional and representational diagram of apparatus for condensing the gaseous portion of a two phase stream, according to a preferred method of the present invention.

space 15, it is possible to increase the stability of the sheet 5 and keep the sheet from coming in contactwith the wall of the tube before it reaches the outlet opening. ,Ifthe nozzle 3jis designed to eject the liquid sheet 5 with a slight conicity, by providing the annularnozzle opening with a corresponding conical shape, the effect of the gas may be advantageously increased. By preventing a premature contact with the condensing tube wall 1, the losses due to friction may be considerably reduced.

It will be understood that the above description of the present invention is susceptible to various modifications, changes, and adaptations.

For example, if instead of a two-phase stream a single-phase stream in the form of a gas is directed into the tapered, rotationally symmetric space, the invention can be used to condense such gas.

lclaim:

l. The method of condensing metallic vapor from a liquid vapor mixture thereof for use with a magnetohydrodynamic generator, comprising introducing a superheated, electrically conductive, metallic liquid into a convergent-divergent nozzle and removing a mixture of metallic vapor and liquid at the outlet thereof, contacting said mixture of metallic vapor and liquid with a surrounding metallic annular converging sheet of liquid, of the same composition, issuing from a coaxial nozzle in a converging condensing tube, introducing a pressurized gas through a nozzle in surrounding relation to the metallic liquid sheet to maintain the liquid in sheet form, and condensing the metallic vapor by the contact of the metallic liquid sheet with the vapor liquid mixture in said converging condensing tube downstream of said convergent-divergent nozzle. 

